High dynamic range image sensor with dual-carrier pixel architecture

Abstract

A high dynamic range camera device has an image sensor that implements readout circuitry to read out, for individual pixels of the sensor, two values that are based on two different types of charge carriers produced in response to a light exposure. The two readout values are read from two floating diffusion nodes of the pixel photodiode designed to collect the two types of charge carriers (electrons and holes). In embodiments, the first readout value is read out by a first readout circuit that provides linear output with respect to the electrical current generated in the photodiode, and the second readout value is read out by a second readout circuit that provides logarithmic output with respect to the current. The two readout values may be selected or averaged to generate high dynamic range pixel data based on changing light conditions.